1. Field of the Invention
One embodiment of the present invention relates to an input/output device, and particularly to a flexible input/output device.
Note that one embodiment of the present invention is not limited to the above technical field. One embodiment of the invention disclosed in this specification and the like relates to an object, a method, or a manufacturing method. One embodiment of the present invention relates to a process, a machine, manufacture, or a composition of matter. Specifically, examples of the technical field of one embodiment of the present invention disclosed in this specification include a semiconductor device, a display device, a light-emitting device, a power storage device, a memory device, an electronic appliance, a lighting device, an input device (e.g., a touch sensor), an output device, an input/output device (e.g., a touch panel), a method for driving any of them, and a method for manufacturing any of them.
In this specification and the like, a semiconductor device generally means a device that can function by utilizing semiconductor characteristics. A semiconductor element such as a transistor, a semiconductor circuit, an arithmetic device, and a memory device are each an embodiment of a semiconductor device. An imaging device, a display device, a liquid crystal display device, a light-emitting device, an electro-optical device, a power generation device (including a thin-film solar cell and an organic thin-film solar cell), and an electronic appliance may each include a semiconductor device.
2. Description of the Related Art
Light-emitting elements utilizing electroluminescence (EL) (such elements are also referred to as EL elements) have features of the ease of being thinner and lighter, high speed response to input signals, and capability of DC low voltage driving and have been expected to be applied to display devices and lighting devices.
Furthermore, a flexible device in which a functional element such as a semiconductor element, a display element, or a light-emitting element is provided over a substrate having flexibility (hereinafter also referred to as flexible substrate) has been developed. Typical examples of the flexible device include a lighting device, an image display device, and a variety of semiconductor circuits including a semiconductor element such as a transistor.
Patent Document 1 discloses a flexible active matrix light-emitting device in which an organic EL element and a transistor serving as a switching element are provided over a film substrate.
Display devices are expected to be applied to a variety of uses and become diversified. For example, a smartphone and a tablet with a touch panel are being developed as portable information terminals.